1. Field of the Invention
The present invention relates to consolidations of powders and methods of consolidating powders.
2. Discussion of the Related Art
The impact consolidation process has been disclosed in numerous patents and patent applications including U.S. Pat. No. 6,915,964 issued to Tapphorn and Gabel, PCT Patent Application WO 02/085532 A1, EP Patent No. 1383610, U.S. Pat. No. 6,074,135 issued to Tapphorn and Gabel, U.S. Pat. No. 5,795,626 issued to Gabel and Tapphorn, U.S. Pat. No. 5,302,414 issued to Alkhimov, et al., and U.S. Pat. No. 6,139,913 issued to Van Steenkiste, et al. None of these patents describe or disclose the benefits of using in-situ shot peening media to enhance the density or modify the residual stresses of coatings or free-form fabricated structures while depositing powder materials using the impact consolidation processes. A recent Patent Application 20060090593 submitted by Liu describes a method of using in-situ non-ductile hard core agglomerate particles to deposit thin layers of coatings using the impact consolidation process called cold spray. Although the method described by Liu results in peening of the substrate to deposit thin coating layers by embedding a portion of the agglomerated metallic particles from the non-ductile hare core particles, it does not disclose a method of using a ductile shot peening media as a co-blended admixture to powders for the purpose of reducing the porosity of coatings or free-form fabricated structures during impact consolidation.
Several patents describe methods of both surface densification of materials and controlling residual stresses by post shot peening processes. U.S. Patent Application 20040197593 by Spoonamore, U.S. Patent Application 20050038516 by Chellappa discusses the use of shot peening as a post deposition process for closing surface pores of cold spray materials.